BIRDS. 
36; 
be insinuated. The feathers are likewise disposed 
in such a manner that the range of the little beards 
of the one, slides, plays, and discovers itself more 
or less under the great beards of the other feather 
that lies over it. A new rank of lesser feathers serves 
as a covering to the quills of the larger, so that the 
air is excluded from every part. 
But as this ceconomy, so admirable in its appoint- 
ment, might be frequently incommoded by rains ; 
the author of nature has furnished birds with an ex- 
pedient that renders their feathers as impenetrable 
to the water, as they are by their structure to the air. 
All birds are provided with two little glands, shaped 
like a nipple, and situated at the extremity of their 
body. This nipple has several little apertures ; and 
when the bird finds her feathers dry, soiled, discon- 
tinued by gaps, or ready to be moistened, she presses 
this nipple with her bill, and forces out an oily 
or unctuous matter, with which these glands are 
filled ; and then drawing her bill over the greatest 
part of her fesithers successively, oils and dresses 
them, gives them a lustre, and fills up all the va- 
cancies with this secreted oil ; after which the water 
only slides over the bird, and finds all the avenues 
to her body perfectly closed. Our poultry, who live 
-Under a covert, have a less quantity of this matter 
than birds who inhabit the open air ; for which rea- 
son a hen, when she is wet, makes a ridiculous 
figure : on the contrary, swans, geese, ducks, moor- 
hens, and all birds destined to live on the water, 
have their feathers dressed with oil from their very 
